1. Technical Field
The present invention relates to a wiper blade configured to be coupled to a wiper device for wiping a windscreen of vehicles, and more particularly to a wiper blade that includes heating elements to allow the wiper blade to wipe a windshield of a vehicle in a suitable operating condition even in a cold winter season.
2. Description of the Related Art
Referring to FIG. 1, a conventional wiper device includes a wiper arm 9 pivoted in right and left directions by a motor (not shown) disposed in a vehicle, and a wiper blade 1 coupled to the wiper arm 9 to move along with the wiper arm 9. The wiper blade 1 is provided with a wiper strip 2 that wipes a glass surface of a windshield (not shown) of the vehicle while reciprocally moving across the windshield in a closely contacting state.
The wiper blade 1 is coupled to the wiper arm 9 and is pivoted at a predetermined angle by operation of the motor. Conventionally, the wiper blade 1 includes a first link member 3 joined to the wiper arm 9, a plurality of second link members 5 joined to the first link member 3 to evenly deliver pressure of the wiper arm 9, and a plurality of third link members 7 respectively joined to the second link members 5 to connect the second link members 5 to the wiper strip 2.
Such conventional wiper blades comprising plural link members are disclosed in U.S. Pat. Nos. 2,596,063 and 5,497,528, DE No. 4,224,866, etc.
Clips 5a and 7a are provided to distal ends of the second and third link members 5 and 7 disposed near the wiper strip 2, and are fitted into a rail groove of the wiper strip 2 to join the wiper strip 2 to the second and third link members 5 and 7, respectively.
The conventional wiper blade 1 includes the plural link members 3, 5 and 7, which are coupled to one another to pivot at predetermined angles, so that the wiper strip 2 made of rubber can be flexibly rounded along the contour of the windshield.
However, the wiper strip 2 tends to contract and become rigidly hardened in a cold winter season. Upon loss of flexibility, the wiper strip 2 does not come into close contact with the windshield surface. Particularly, both ends of the wiper strip 2 are slightly separated from the windshield surface, which causes a reduction in contact area between the wiper strip and the windshield surface.